Walking on Air

Meaning:
To be so happy that you feel like you’re floating.

Example:
Raj felt like he was walking on air when he was finally promoted after five years in service.

Did you know?
‘Walking on Air’ is also the name of a Scottish charity. It provides opportunities for people with disabilities to fly via modified gliders.

Reference: http://idioms.thefreedictionary.com/walk+on+air